Control apparatus for breathing apparatus



5 31, 3969 K. FREYTAG 3,426,794

CONTROL APPARATUS FOR BREATHING APPARATUS Filed Sept. 26, 1966 INVENTOR Klaus Fr'e ytay BY v W K 3 United States Patent 3,426,794 CONTROL APPARATUS FOR BREATHING APPARATUS Klaus Freytag, Lubeck, Germany, assignor to Otto Heinrich Drager, Lubeck, Germany Filed Sept. 26, 1966, Set. No. 582,005 Claims priority, application Germany, Sept. 29, 1965,

D 48,312 U.S. Cl. 137-607 6 Claims Int. Cl. A62b 9/02, 7/00 ABSTRACT OF THE DISCLOSURE This invention relates to a control apparatus for a breathing apparatus and in particular for regulating the pressureapplied to the air exhaled by a person.

Various types of breathing apparatuses have been used in which air is intermittently forced into the lungs of a patient, and in certain types of such apparatus the air is withdrawn in alternate time periods to exhale the air from the patient. In such a case, the apparatus can be provided with a breathing 'bag contained in a housing, the interior of which is alternately placed under greater than and/or less than atmospheric pressure. The maximum of expansion of the breathing bag is, in this case, limited by an adjustable stop.

During a continuous breathing with this type of apparatus, it is possible that lung collapse (atelectasis) can occur because the breathing is always very uniform as disclosed in German Patent DBP 1,126,073.

A breathing apparatus is also used in which an air inhaling intake line forces compressed air intermittently into the patients lungs and having an exhale exhaust air line provided with a valve including a closure mechanism which holds the valve closed during one breathing cycle at a definite time interval This can be done only by mechanical or electrical means. Such an apparatus can be provided with a counting device which holds the valve closed for one entire breathing cycle and after a definite and adjustable number of inhalings and exhalings of the air for the patient. Because of the throttling of the valve, it is possible that an insufficient exhaling occurs for one exhaled breath so that during the next inhaling of air at above atmospheric pressure the lungs receive more air and, in efiect, produce a deep breath.

The object of this invention is to produce an apparatus in which the resistance to the exhaling of air from the patient is moved from a negative to a positive pressure area so that the pressure for the ex'haling of air can be adjusted and at the same time the exhaled air exhaust valve can be set at different time intervals to a higher varying and opening pressure. In this invention, a control device is connected to the exhaled air line of the breathing apparatus and especially for a narcotic administering apparatus. This control device or apparatus is composed of a spindle adjustably threaded in a casing and provided With a first valve head for closing a port in the apparatus 'housing leading to the atmosphere and also carrying a second valve head for closing the exhale air line under the pressure of a spring. The casing is also under a second spring pressure to urge it in a direction to open the second valve head and is joined to a membrane which, on one side, communicates with the greater than atmospheric pressure of the breathing apparatus. Thus this apparatus has the advantage in that the resistance to the exhaled breath of the patient can be adjustable to ditferent greater than and/or less than atmospheric pressures. This also makes it possible to avoid liquid collecting in the lungs and atelectasis. This apparatus can also be used to inflate the patients lungs.

The means by which the objects of the invention are obtained are described more fully with reference to the accompanying schematic drawing which shows a crosssectional view through the control apparatus.

The entire breathing apparatus, not shown, contains an exhale air line leading, for example, from a face mask to a pump for producing greater than and less than atmospheric pressures. The control apparatus of this invention is connected into this exhale air line and is composed of an exhaled air duct 1 in a housing 2, 'which duct is connected to the negative or less than atmospheric pressure pipe joined to the pump P. This lduct which extends through the housing communicates with a port 3 in the housing leading to the atmosphere. The other side of the housing has a duct 4 communicating with the pipe leading to the face mask. The middle of the housing is divided by partitions 5 and 6 between which is a flexible membrane 7 for forming a chamber 8. The membrane is fastened to the wall of the chamber. A duct 9 communicating with the chamber 8 is joined to a pipe leading to the positive or greater than atmospheric pressure side of the pump P and contains a control valve, not shown, which is opened from time to time during the breathing cycle.

Duct 1 is extended through chamber 10 and by-pass duct 11 to a chamber 12 which communicates with the exhaled air duct 4. The partitions 5 and 6 each have an opening through which a threaded casing 13* extends land is fastened to membrane 7. Spindle 14 is threaded in casing 13 and is extended by shaft 15 outwardly of the housing to a knob 16. Shaft 15 carries a collar forming a. first valve head 17 (which is seatable upon port 3 for closing the port as shown in the drawing. On the other hand, spindle I14 is extended by the pin 18- which carries a movably mounted ring 19 forming a second valve head and which is urged by the pressure of first spring 20 in a direction for closing the exhaled air duct 4. The spring also bears on a flange 21 secured to pin 18. The movement of valve head 19 is limited by a stop head 22 secured to the end of pin 18. Valve head 19 is adapted to close against valve seat 23 surrounding the duct 4.

Casing 13 has a flange or shoulder 24 which, as shown in the drawing, lies under the pressure of spring 25 to bear upon partition 6.

Port '3 is surrounded by a threaded neck 26 holding a limit nut 27.

In the position of the apparatus as shown, the duct 4 communicates through the face mask with the patients lungs and the chambers 10 and -12 communicate with the duct 1 leading to the negative atmospheric pressure side of the pump P. When the patients lungs are to be subjected to not so much negative exhale pressure, a change is made by turning knob 16 to raise first Ivalve head 17 and opening port 3 so atmospheric air can flow into the housing and the amount of negative exhale air pressure adjusted as desired at that moment. The port is further opened by turning the knob. A second valve head 19, during still further turning of the spindle 14, causes the second valve head 19 to close against valve seat 23 so that the patient then must exhale against a positive pressure. This pressure is increased still more by the pressure of the first compression spring 20 which is expanded by the turning of the spindle 14.

Also, chamber 8 is periodically in communication with the positive or greater than atmospheric pressure coming from the pump P through a control valve so that casing 113 is displaced toward second valve head 19 and valve seat 23. The opening resistance of the valve is thus increased. The distance the casing 13 and spindle 14 are displaced, together with the parts fixed thereto, depends upon how much the periodic resistance to the exhaling of air is to be adjusted. This adjustment is accomplished by the turning of the limit nut 27 which acts as a stop for the knob 16.

Having now described the means by which the objects of the invention are obtained,

I claim:

1. A control apparatus for the exhaled air line of a breathing apparatus such as used for administering narcotics comprising a housing, port means in said housing for the entry of atmospheric air, an exhaled air duct in said housing adapted to communicate between the exhaled air line and the negative pressure side of a positive and negative pressure pump, a casing mounted in said housing, a spindle threaded in said casing, a collar attached to said spindle and forming a first valve head adapted to be seated on said port means, a second v-alve head movably mounted on said spindle, first spring means for urging said second valve head toward an end of said spindle in a direction to close said exhaled air duct in said housing, second spring means for urging said casing in a direction for opening said exhaled air (duct, and membrane means in said housing and secured to said casing for forming a chamber adapted to communicate with the positive pressure side of said pump.

2. An apparatus as in claim 1, further comprising a partition in said housing, a flange means on said casing engageable with said partition for limiting the movement of said casing in one direction.

3. An apparatus as in claim 2, further comprising said second spring means bearing on said flange means for urging said flange means into engagement with said partition.

4. An apparatus as in claim 3, further comprising a pin extension joined to said spindle, and said second valve head comprising a ring slidably mounted on said pin extension.

5. An apparatus as in claim 4, further comprising limit stop means attached to said housing for limiting the threaded movement of said spindle in said casing.

6. An apparatus as in claim 5, said limit stop means comprising a nut threaded to the exterior of said housing, and knob means attached to said spindle for engagement 'with said nut to limit the threaded movement of said spindle in said casing.

References Cited UNITED STATES PATENTS 3,099,290 7/1963 Chatham et a1. l37607 NATHAN L. MINTZ, Primary Examiner.

US. Cl. X.R. 128-1455 

